package lab02.test28;

import java.util.InputMismatchException;
import java.util.Scanner;

public class Test {
    public static void main(String[] args) {
        Scanner scanner =new Scanner(System.in);

            double x=0;
            try{
                x = scanner.nextDouble();
            }catch (InputMismatchException e){
                System.out.println("输入半径的类型错误");
            }
            System.out.println("圆的面积为" + "s=" + x * x * 3.14);

    }
}
